Pooled AALL0434 plus AALL1231 EFS, OS, and CIR by CNS status. (A) Four-year EFS: CNS-1, 85.1% ± 1.0%; CNS-2, 83.2% ± 2.0%; and CNS-3, 71.8% ± 4.0% (P = .0004). (B) Four-year OS: CNS-1, 90.1% ± 0.8%; CNS-2, 90.5% ± 1.6%; and CNS-3, 82.7% ± 3.4% (P = .005). (C) Four-year CIR: CNS-1, 7.6% ± 0.7%; CNS-2, 9.9% ± 1.4%; and CNS-3, 17.9% ± 3.1% (P = .0002). (D) Four-year CIR of isolated CNS relapse: CNS-1, 1.8% ± 0.3%; CNS-2, 4.1% ± 1.0%; and CNS-3, 10.8% ± 2.5% (P < .001). (E) Four-year CIR of isolated marrow relapse: CNS-1, 3.2% ± 0.5%; CNS-2, 2.3% ± 0.7%; and CNS-3, 4.0% ± 1.6% (P = .466). (F) Four-year CIR of combined CNS and marrow relapse: CNS-1, 0.9% ± 0.2%; CNS-2, 1.6% ± 0.6%; and CNS-3, 0.6% ± 0.6% (P = .603). BM, bone marrow.